of possible universes that has been actualized or that will, at some point, be actualized.
Finally, in the case of the ethical problem that the theistic proponent of multiverse models that entail the actualization of all possible states of affairs it faces, the theist will have to explain just how a traditional conception of morality can be maintained or if it needs to be maintained at all, in such a multiverse model. The issue is that, for an agent, his motivation for doing morally good acts may become diminished, trivialized, or altogether lost since, whether he does the morally good act or not, it will be actualized in some universe within the multiverse by either himself or one of his counterparts. Robert Adams captures the sentiment of this problem in writing that any particular agent in any particular universe could reasonably ask himself “[w]hat is wrong with actualizing evils, since they will occur in some other possible [universe] anyways if they don’t occur in this one” (1979, p. 195). Likewise, an agent’s refusal to commit some morally evil act will only make it so that that evil does not occur in his particular universe, which will further entail that that same evil that he refused to actualize will be actualized by one of his counterparts in some other part of the multiverse. The possible conclusion that stems from this is that it appears to trivialize all of our ethical considerations since whatever we do, or don’t do, will entail the opposite outcome in some other universe. On this, the motivation to perform morally good actions is seemingly lost since the agent could adopt an “if I don’t do it another version of me will” sort of attitude, as is discussed by Adams (1979). David Lewis, however, replies to such a worry as directed at modal realism, but what he says about modal realism can be applied to our case of the multiverse as well. He argues that
For those of us who think of morality in terms of virtue and honour, desert and respect and esteem, loyalties and affections and solidarity, the other-worldly evils should not seem even momentarily relevant to morality. Of course, our moral aims are egocentric. And likewise, all the more for those who think of morality in terms of rules, rights and duties; or as obedience to the will of God. (Lewis, 1986, p. 127)
Of course, such a reply is not readily accepted by everyone, and Yujin Nagasawa argues that the kind of reply provided by Lewis does not adequately solve the problem. Of such a reply, Nagasawa writes
However, if the multiverse model in question is correct, it is difficult not to extend our concerns to other possible universes in our context because even if people in other possible universes are morally irrelevant to what we do in our universe they nevertheless exist and form part of God as the totality. (Nagasawa, 2015, p. 188)9
While ethical and moral issues of the kind faced by modal realists will have to be addressed by any multiverse theory, this is something that the theistic multiverse proponent will be harder-pressed to provide a response to and discuss how his model will deal with certain ethical considerations. A theistic multiverse account has the added layer and factor of God, and how ethics and morality relate to Him, to navigate whereas nontheistic multiverse accounts do not have this hurdle to deal with and thus can potentially avail themselves of many more possible responses.
The Multiverse Entailment of Deism
Now that several of the potential drawbacks that theists may face in accepting particular multiverse theories have been discussed, the attention now turns to how and why I think that the adoption of a specific kind of multiverse theory may entail deism if the proponent of the multiverse theory aims to maintain the existence of God. For purposes of clarity, I would like to specify the kind of multiverse model that I will be referring to, moving forward. It appears that most, if not all, of the strongest multiverse theories put forth by both science and philosophy entail the existence of all possible universes. There are two distinctions that differentiate each of these theories from one another, however. The first distinction is that each theory proposes its conception of how these universes exist in relation to one another. That is to say, these theories will vary in their explanations of the degree to which the universes within the multiverse are spatiotemporally distinct and isolated from each other, how and when the universes come to exist, how these multiple realities come to be actualized, and other similar factors. The second way in which these multiverse theories vary is in their conceptions of what exactly constitutes “possible” when referring to a possible universe. Some conceptions may argue that only universes that contain sentient life are possible, some may argue that only universes that possess a certain amount of goodness or happiness are possible, some may argue that any conceivable and logically possible universe is possible, while still others may argue that only universes that adhere with particular physical constants are possible. The variations among what ought to confer possibility upon a universe are wide and divergent, and this remains one of the most debated aspects of the multiverse discussion. When referring to the multiverse for the remainder of this project, unless otherwise indicated, the type of multiverse that is being referred to is this general kind that includes and exhausts all possible universes. That is to say, multiverses that entail the actualization, by whatever means and processes, of every possible universe, be it simultaneously, cyclically, part of an infinite sequence or any other mode. The key is that the multiverse models to which I refer when using the term “multiverse” are those that include, in some capacity, the actualization of all metaphysically possible universes. The individual conception of the relations of the universes to one another, as well as the conception of what exactly constitutes a possible universe, are not of extreme importance in this case since all types of these multiverse theories ultimately entail the same preference of a deistic God over the God of classical Judeo-Christian monotheism. So, while in this discussion, I will be speaking of an “all possible realities exist” kind of multiverse that is akin to modal realism (Lewis, 1986). This is done simply for the purposes of inclusion. What this means is that if my arguments seem plausible on this most extreme account of the multiverse, then surely it will plausibly transfer onto other brands of multiverse that happen to fall within this highly inclusive multiverse model. What I mean by “fall within” is that on the account that I am employing, very little (if any) restrictions are placed on what entails a possible universe, so any multiverse model that does propose any sort of definition that excludes some universes as impossible would be a multiverse that necessarily contains a numerically smaller amount of universes than does my inclusive model.10 Any of those restrictions would then have to be argued for on their own basis, independently of my deistic argument. For example, suppose that the inclusive multiverse model contains 10,000 individual universes within it, and through all of these universes, every possible universe has been actualized. Now, if we take another multiverse model, let us call it Multiverse C, that includes a threshold claiming that only those universes that include sentient beings are truly possible, and thus are the only ones that can be included in the multiverse. Given this threshold, Multiverse C may contain only 5,000 individual universes.11 Similarly, we can imagine another multiverse model, Multiverse D, that accepts as possible only those universes that contain sentient beings and that are also on-balance good, this model would contain only, perhaps, 3,000 individual universes. So, if my proposed arguments work on the level of the inclusive multiverse, since I make no claims as to whether a threshold for conference of existence really exists or, if it does exist, where it should be, any other multiverse models, such as those exemplified by Multiverse C or Multiverse D, would simply yield less individual universes for my proposal to range over. This is not a problem at all. The difference between multiverse models, for the scope of this project, is only that each one will include a different number of individual universes within it, and I have simply chosen the model that entails the largest number of individual universes within it to allow for my argument to range as broadly as possible.
The adoption of such a multiverse theory, for anyone who desires to maintain the existence of God, appears to be an ontological view in which this God would not be required to, or even feel compelled to, act in the natural world in any way aside from the initial act of creation. The reason for which an active God would be superfluous on a view such as this is that, given the fact that every possible universe is/was/will be actualized either at some particular time or at some particular space, this would entail that every possible state of affairs is/was/will be actualized as well. Given this, everything possible will happen
